The subject matter disclosed herein relates to X-ray imaging systems having C-arms and, more particularly, to orbital rotation positioning devices for the C-arms.
Medical diagnostic imaging systems generate images of an object, such as a patient, for example, through exposure to an energy source, such as X-rays passing through a patient, for example. The generated images may be used for many purposes. Often, when a practitioner takes X-rays of a patient, it is desirable to take several X-rays of one or more portions of the patient's body from a number of different positions and angles, and preferably without needing to frequently reposition the patient. To meet this need, C-arm X-ray diagnostic equipment has been developed. The term C-arm generally refers to an X-ray imaging device having a rigid and/or articulating structural member having an X-ray source and an image detector assembly that are each located at an opposing end of the structural member so that the X-ray source and the image detector face each other. The structural member is typically “C” shaped and so is referred to as a C-arm. In this manner, X-rays emitted from the X-ray source can impinge on the image detector and provide an X-ray image of the object or objects that are placed between the X-ray source and the image detector.
In many cases, C-arms are connected to one end of a movable arm. In such cases, the C-arm can often be raised and lowered, be moved from side to side, and/or be rotated about one or more axes of rotation. Accordingly, such C-arms can be moved and reoriented to allow X-ray images to be taken from several different positions and angles and different portions of a patient, without requiring the patient to be frequently repositioned. For example, the C-arm may be rotated in an orbital direction to a desired position (e.g., orbital angular position). However, if it desired to return to this position later, the position may need to be remembered (e.g., using a scale on the C-arm) or temporarily marked on the C-arm. To return to the desired position involves careful hand/eye coordination to ensure accuracy, which may be slow, tedious, and unreliable.